Siren



FIG. 1 is a front, top, right side perspective view of a first embodiment of a siren showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a right side view thereof; and,

FIG. 7 is a left side view thereof.

The broken lines, and the subject matter disclosed inside the broken lines, illustrate portions of the siren that form no part of the claimed design. 

CLAIM The ornamental design for a siren, as shown and described. 